US11977323B2ActiveUtilityA1
Optical system and image pickup apparatus having the same
Est. expiryNov 18, 2040(~14.4 yrs left)· nominal 20-yr term from priority
Inventors:Yuki Matsuba
G03B 5/04G02B 27/0068G02B 27/646G03B 2205/0015G02B 9/64
44
PatentIndex Score
0
Cited by
7
References
19
Claims
Abstract
An optical system includes first and second lens units configured to move to have a component of direction perpendicular to an optical axis, in which a sign of an amount of movement of the lens units is defined as negative for a moving direction of the first lens unit and as positive for an opposite direction to the moving direction of the first lens unit, a product of an amount of movement and a focal length of the first lens unit and a product of an amount of movement and a focal length of the second lens unit are different from each other in sign, and Petzval sums of the first and second lens unit, a focal length of the optical system, and a back focus of the optical system are set.
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1. An optical system comprising:
a first lens unit configured to move to have a component of direction perpendicular to an optical axis;
an intermediate lens unit; and
a second lens unit configured to move to have a component of direction perpendicular to the optical axis,
wherein the intermediate lens unit is composed of all lenses disposed between the first lens unit and the second lens unit, and the intermediate lens unit is not movable in the direction perpendicular to the optical axis,
wherein the first lens unit and the second lens unit are moved in directions different from each other in case where focal lengths of the first lens unit and the second lens unit are same in sign, and the first lens unit and the second lens unit are moved in a same direction in case where the focal lengths of the first lens unit and the second lens unit are different from each other, and
wherein the following inequalities are satisfied,
0.4<| Pa 51 +| Pb |<12.0,
0< Lbk/f< 0.65, and
−0.5< fa/fbw< 4.0
where Pa represents a product of a Petzval sum of the first lens unit and a focal length of the optical system, Pb represents a product of a Petzval sum of the second lens unit and the focal length of the optical system, f represents a focal length of the optical system, Lbk represents a back focus of the optical system, fbw represents a focal length of the intermediate lens unit, and fa represents a focal length of the first lens unit.
2. The optical system according to claim 1 , wherein a sign of a product of a decentering aberration coefficient representing a sensitivity of image plane tilt to a parallel decentering of the first lens unit to the optical axis and the amount of movement of the first lens unit is the same as a sign of a product of a decentering aberration coefficient representing a sensitivity of image plane tilt to a parallel decentering of the second lens unit to the optical system and the amount of movement of the second lens unit.
3. The optical system according to claim 1 , wherein the following inequality is satisfied,
0
<
|
(
IIIEa
×
Sb
)
-
(
IIIEb
×
Sa
)
|
<
6.0
where IIIEa represents a decentering aberration coefficient representing astigmatism caused by a parallel decentering of the first lens unit to the optical axis, IIIEb represents a decentering aberration coefficient representing astigmatism caused by a parallel decentering of the second lens unit to the optical axis, Sa represents a decentration sensitivity of the first lens unit, and Sb represents a decentering sensitivity of the second lens unit.
4. The optical system according to claim 1 , wherein the following inequality is satisfied,
0
<
|
(
IIEa
×
Sb
)
-
(
IIEb
×
Sa
)
|
<
2
.
5
where IIEa represents a decentering aberration coefficient representing a comatic aberration caused by a parallel decentering of the first lens unit to the optical axis, IIEb represents a decentration aberration coefficient representing a comatic aberration caused by a parallel decentering of the second lens unit to the optical axis, Sa represents a decentering sensitivity of the first lens unit, and Sb represents a decentering sensitivity of the second lens unit.
5. The optical system according to claim 1 , wherein the following inequality is satisfied,
0.5
<
Pa
/
Pb
<
2.0
.
6. The optical system according to claim 1 ,
wherein a magnification of the first lens unit and a magnification of the intermediate lens unit are different from each other in sign.
7. The optical system according to claim 1 , wherein the following inequality is satisfied,
0
.
0
7
<
fa
/
f
<
2.0
8. The optical system according to claim 1 , wherein the following inequality is satisfied,
0.07
<
fb
/
f
<
2.0
where fb represents a focal length of the second lens unit.
9. The optical system according to claim 1 , comprising an aperture stop;
wherein the following inequality is satisfied,
0
<
|
LshA
/
Lopt
|
<
0
.
5
where Lopt represents a total length of the optical system and LshA represents a length from the aperture stop to a surface of the first lens unit disposed farthest from the aperture stop.
10. The optical system according to claim 1 , comprising an aperture stop;
wherein the following inequality is satisfied,
0
<
|
LshB
/
Lopt
|
<
0.5
where Lopt represents a total length of the optical system and LshB represents a length from the aperture stop to a surface of the second lens unit disposed farthest from aperture stop.
11. The optical system according to claim 1 , wherein the following inequality is satisfied,
0
.
0
1
<
|
Ma
max
|
/
φ
a
<
0.5
where φa represents an effective diameter of the first lens unit and Ma max represents a maximum movement amount of the first lens unit in a vertical direction to the optical axis.
12. The optical system according to claim 1 , wherein the following inequality is satisfied,
0
.
0
1
<
|
Mb
max
|
/
φ
b
<
0.
5
where φb represents an effective diameter of the second lens unit and Mb max represents a maximum movement amount of the second lens unit in a vertical direction to the optical axis.
13. The optical system according to claim 1 , wherein the following inequality is satisfied,
0.5
<
Lopt
/
f
<
3.0
where Lopt represents a total length of the optical system.
14. An image pickup lens unit, comprising an optical system and an image pickup element configured to receive an image formed by the optical system,
wherein the optical system comprises:
a first lens unit configured to move to have a component of direction perpendicular to an optical axis;
an intermediate lens unit, and
a second lens unit configured to move to have a component of direction perpendicular to the optical axis,
wherein the intermediate lens unit is composed of all lenses disposed between the first lens unit and the second lens unit, and the intermediate lens unit is not movable in the direction perpendicular to the optical axis,
wherein the first lens unit and the second lens unit are moved in directions different from each other in case where focal lengths of the first lens unit and the second lens unit are same in sign, and the first lens unit and the second lens unit are moved in a same direction in case where the focal lengths of the first lens unit and the second lens unit are different from each other, and
wherein the following inequalities are satisfied,
0.4<| Pa|+|Pb|< 12.0,
0< Lbk/f< 0.65, and
−0.5< fa/fbw< 4.0
where Pa represents a product of a Petzval sum of the first lens unit and a focal length of the optical system, Pb represents a product of a Petzval sum of the second lens unit and the focal length of the optical system, f represents a focal length of the optical system, Lbk represents a back focus of the optical system, fbw represents a focal length of the intermediate lens unit, and fa represents a focal length of the first lens unit.
15. The image pickup lens unit according to claim 14 , wherein a sign of a product of a decentering aberration coefficient representing a sensitivity of image plane tilt to a parallel decentering of the first lens unit to the optical axis and the amount of movement of the first lens unit is the same as a sign of a product of a decentering aberration coefficient representing a sensitivity of image plane tilt to a parallel decentering of the second lens unit to the optical system and the amount of movement of the second lens unit is the same.
16. The image pickup lens unit according to claim 14 , wherein the following inequality is satisfied,
0
<
|
(
IIIEa
×
Sb
)
-
(
IIIEb
×
Sa
)
|
<
6.0
where IIIEa represents a decentering aberration coefficient representing astigmatism caused by a parallel decentering of the first lens unit to the optical axis, IIIEb represents a decentering aberration coefficient representing astigmatism caused by a parallel decentering of the second lens unit to the optical axis, Sa represents a decentration sensitivity of the first lens unit, and Sb represents a decentering sensitivity of the second lens unit.
17. The image pickup lens unit according to claim 14 , wherein the following inequality is satisfied,
0
<
|
(
IIEa
×
Sb
)
-
(
IIEb
×
Sa
)
|
<
2.5
where IIEa represents a decentering aberration coefficient representing a comatic aberration caused by a parallel decentering of the first lens unit to the optical axis, IIEb represents a decentration aberration coefficient representing a comatic aberration caused by a parallel decentering of the second lens unit to the optical axis, Sa represents a decentering sensitivity of the first lens unit, and Sb represents a decentering sensitivity of the second lens unit.
18. The image pickup lens unit according to claim 14 , wherein the following inequality is satisfied,
0.5
<
Pa
/
Pb
<
2.0
.
19. The image pickup lens unit according to claim 14 ,
wherein a magnification of the first lens unit and a magnification of the intermediate lens unit are different from each other in sign.Cited by (0)
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